Ispro, TVTonic runs beautifully on my Internet Explorer. I have Vista, but it's Business (no Media Center). I did install Silverlight after I had installed and used TVTonic, but noticed no difference. TVTonic also runs on IE on Windows XP.
You could be right though that the newest version needs Silverlight for the ultimate TVTonic experience, or within Vista Media Center it must use Silverlight.
Whatever, TVTonic beats the heck out of lousy streaming video.